1. Field of the Invention
The present invention generally relates to the transportation of heated reagents to a chemical reactor. More particularly, it relates to the transportation of heated reagents in the synthesis of nano-particle-based materials.
2. Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Quantum dots (QDs) consist of tiny particles (nanoparticles) of semiconductor material with dimensions on the order from 2 to 50 nanometers. Because of their size these particles have unique electrical properties, one of which is the emission of visible light under excitation. The color of the light emitted is dependent upon the size of the QD particle. By precisely controlling the size of the particles during manufacture, the color of the light emitted may also be precisely controlled, making quantum dots useful in commercial applications such as optical and electronic devices and other applications ranging from biological labelling, photovoltaics, catalysis, biological imaging, LEDs, general space lighting, and electroluminescent displays amongst many new and emerging applications.
A method of QD manufacture involves producing nanoparticles from chemical precursors in the presence of a molecular cluster compound under conditions whereby the molecular cluster acts as a prefabricated seed template for the formation of a core semiconductor material. One or more semiconductor shell layers may be grown on the core material. See, for example, U.S. Pat. No. 8,524,365 the entirety of which is hereby incorporated by reference.
As shown in the system of FIG. 1, during QD manufacture, reactants in a reservoir 110 may be added to a reactor 100 by use of a pump 120. The reaction (or individual reactants) may be sensitive to the presence of oxygen in the system, and an inert gas such as nitrogen, for example, may be used to purge the system. The inert gas may be introduced to the system via a purge line 140 and opening a gas source valve 130. Reactants may be in the form of a slurry. In some cases, heating the slurry may cause it to form a solution, in whole or in part. Heating a slurry of reactants may make the slurry more uniform prior to its addition to a reactor.
Line jacketing is commonly used to maintain the temperature of a liquid or slurry within such delivery systems. In these systems the jacket typically contains an electrical heating element to warm the liquid or slurry by electrical conduction via the pipe or the jacket, for example, using heating tape or heating cable.
Delivery lines may be made of a transparent material such as glass to allow viewing of the reactants and observation and detection of blockages, for example. However, jacketed heating means may obstruct the view of the transparent lines, and prevent an operator from seeing if and where a blockage might occur. Thus, a method to heat the slurry within the lines and without obscuring the view of the flow through the system is needed.